KEVIN Rudd is putting off an election date decision as he uses this week to flush out the Opposition on its economic policy.

The Government believes Opposition Leader Tony Abbott is not ready to explain how he could afford his policies, while it has its own problems keeping the Budget under control.

The Prime Minister is prepared to wait and leading pollster David Briggs of Galaxy believes his electoral stocks could go up in this unusual, unofficial election campaign.

"I wouldn't be willing to write Kevin Rudd and Labor off in terms of further growth,'' said Mr Briggs today, after polling showing the ALP at 40 per cent of primary votes, a three year high, to the Opposition's 44 per cent.

But the odds are moving firmly in favour of September 7, with an announcement this weekend.

Mr Rudd would decline to attend the G20 summit in Russia on September 5 and 6 even though Australia assumes presidency of the organisation and hosts it next year.

Labor is also buoyed by a Galaxy finding that the Government and the Opposition are rated equally by voters on economic management - 41 per cent each.

This is a breakthrough for Mr Rudd who wants to pressure the Opposition to come up with costings for its policies.

The Government has its own problems propping up the Budget as revenues have continued to decline faster than anticipated in the May economic statement.

The Expenditure Revue Committee met this morning and cabinet this afternoon will be briefed on the basics of an economic statement to be released by Treasurer Chris Bowen towards the end of the week.

The Government knows that if it is having difficulties, the situation would be worse for the Opposition as it prepares to cost its election policies.

Deputy Prime Minister Anthony Albanese led the strategy today with claims the Opposition would have to slash spending and risk employment while the Government would deliver a Budget surplus "over time but not in a way that would damage economic growth and destroy jobs".

The issue could come down to who voters believe will keep their promises.

"Certainly on the question of the person voters trust to keep their election promises, Kevin Rudd leads Tony Abbott on that by a margin of 37 (per cent) to 32,'' said Mr Briggs.

"So it really comes down to trust in the political leaders, rather than their actual policies.''

Mr Briggs said the trust factor favouring Mr Rudd would not change "any time soon''.